For this project, we were asked to solve the murder of Carleton Comet, who had been stabbed at a picnic with his friends, using forensic science. We were equipped with a crime report, each suspect's family histories, samples from the knife, blood samples from each suspect, a fingerprint found on a glass table near the murder, and a death note with three pens, belonging to various suspects, that read, "You are a dead man." To solve this case, I teamed up with Evan Colenbrander and John Walsh.
The Presentation
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In this presentation, we revealed who we are charging and why we charged them.
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DNA Structure & Replication
Structure
DNA has 2 core parts. The backbone of the DNA, which is made of sugar-phosphate, is connected to the outer end of each base pair. The bases, the other core feature, have four different types; A, T, C, and G. A is for adenine, T is for thymine, C is for cytosine, and G is for guanine. |
Replication
The process of DNA replication involves many different enzymes that preform complicated tasks to limit the amount of mistakes in DNA. First, the enzyme Helicase comes through and unzips the original DNA strand from 5' to 3'. This separates the strand into two half-strands, the leading strand and the lagging strand. The leading strand is easy to complete. First, the RNA Primase puts a primer on the 5' end of the leading strand so the next enzyme, the DNA Polymerase, can go through and complete the strand, in the 5' to 3' direction. The lagging strand is a little more tricky, because the DNA Polymerase can only go in the 5' to 3' direction, and the lagging strand goes from 3' to 5'. The RNA Primase needs to put multiple primers down in different places along the strand so that the DNA Polymerase can connect the strand from 5' to 3'. These are called Okazaki fragments. The DNA Polymerase then connects these Okazaki fragments and a new DNA strand is formed. These new strands are called semi-conserved because they contain half of the old strand and half of a new one. |
Diseases in the Case
There were many different diseases and chromosomal disorders found in the suspects of this case, as well as their families. Here are some explanations of each disease.
Huntington's Disease: Huntington's Disease is a deterioration of brain cells in the brain. It is usually seen later in life and symptoms include memory loss.
Marfan Syndrome: Marfan Syndrome is a genetic disorder of the connective tissue. Symptoms include long slender fingers, disproportionately long limbs, and and indented breast plate.
Down Syndrome: Down Syndrome is a chromosomal disorder caused by an extra 21st chromosome, that is found in both men and women. Down Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being taller than average, learning difficulties, and weak muscles.
Jacob's Syndrome (XYY Karyotype): Jacob's Syndrome is a chromosomal disorder caused by an extra Y chromosome, that is only found in men. Jacob's Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive. Symptoms include slanted eyes, a flattened facial profile, and a poor muscle tone.
Triple X Syndrome (XXX Karyotype): Triple X Syndrome is a chromosomal disorder caused by an extra X chromosome, that is only found in women. Triple X Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being taller than average, flat feet, and seizures.
Klinefelter (XXY Karyotype): Klinefelter is a chromosomal disorder caused by an extra X chromosome, that is only found in men. Klinefelter is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being skinnier than average, being more feminine, and less facial hair.
Achondroplasia: Achondroplasia is a form of short-limbed dwarfism caused by a malfunction in the FGFR3 gene. Symptoms include short stature and smaller than average limbs.
Marfan Syndrome: Marfan Syndrome is a genetic disorder of the connective tissue. Symptoms include long slender fingers, disproportionately long limbs, and and indented breast plate.
Down Syndrome: Down Syndrome is a chromosomal disorder caused by an extra 21st chromosome, that is found in both men and women. Down Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being taller than average, learning difficulties, and weak muscles.
Jacob's Syndrome (XYY Karyotype): Jacob's Syndrome is a chromosomal disorder caused by an extra Y chromosome, that is only found in men. Jacob's Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive. Symptoms include slanted eyes, a flattened facial profile, and a poor muscle tone.
Triple X Syndrome (XXX Karyotype): Triple X Syndrome is a chromosomal disorder caused by an extra X chromosome, that is only found in women. Triple X Syndrome is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being taller than average, flat feet, and seizures.
Klinefelter (XXY Karyotype): Klinefelter is a chromosomal disorder caused by an extra X chromosome, that is only found in men. Klinefelter is caused by a mutation in the DNA sequence and is neither dominant nor recessive as it is not inherited. Symptoms include being skinnier than average, being more feminine, and less facial hair.
Achondroplasia: Achondroplasia is a form of short-limbed dwarfism caused by a malfunction in the FGFR3 gene. Symptoms include short stature and smaller than average limbs.
DNA Mutations
DNA Mutations are random occurrences in the DNA sequence that can have catastrophic results. There are 8 main types of DNA Mutations. They are transition, transversion, silent, missense, nonsense, repeat expansion, base substitution, insertion, and deletion.
Other Concepts
Gene: a code that produces a specific trait in an organism.
Allele: a variation of a gene.
Chromosome: A structure of nucleic acids that carry genetic information.
Phenotype: Physical characteristics expressed by a gene.
Genotype: The genetic characteristics expressed by a gene.
Dominant: A trait that is shown when present.
Recessive: A trait that is shown when it is the only trait present.
Co-dominant: When two dominant traits are expressed at the same time.
Incomplete Dominant: When a trait is not completely expressed.
Heterozygous: When two different alleles are present.
Homozygous: When the same allele is present multiple times.
Fingerprinting: The process of finding fingerprints and matching them to real people.
Ink Chromatography: The process of finding the dyes in the ink from a pen.
Pedigrees: Family trees showing deaths, gender, and diseases.
DNA Fingerprinting: The process of identifying the DNA in blood.
Karyotypes: The number and letter value assigned to chromosomes.
Allele: a variation of a gene.
Chromosome: A structure of nucleic acids that carry genetic information.
Phenotype: Physical characteristics expressed by a gene.
Genotype: The genetic characteristics expressed by a gene.
Dominant: A trait that is shown when present.
Recessive: A trait that is shown when it is the only trait present.
Co-dominant: When two dominant traits are expressed at the same time.
Incomplete Dominant: When a trait is not completely expressed.
Heterozygous: When two different alleles are present.
Homozygous: When the same allele is present multiple times.
Fingerprinting: The process of finding fingerprints and matching them to real people.
Ink Chromatography: The process of finding the dyes in the ink from a pen.
Pedigrees: Family trees showing deaths, gender, and diseases.
DNA Fingerprinting: The process of identifying the DNA in blood.
Karyotypes: The number and letter value assigned to chromosomes.
Reflection
Looking back on the project, it was definitely a great learning experience for me. The investigation portion of the project went well. My group was able to find good evidence and work towards putting it together into a case. This part of the project taught me about forensic science and the world of criminal investigation. However, there were definitely a few bumps in the road. One example of this is our petty squabbles. Although, we got along overall and were able to build a solid case, we would fight over dumb stuff, such as who would get the case file at the beginning of the day. This taught me about collaboration. Another peak came when we delivered the presentation. The judges understood what we said and we were able to answer their questions. This part of the project taught me about public speaking and helped me understand professional viewpoints on criminal cases. Another pit occurred in the absences from the project. During this project, there were a few trips from other classes and people calling in sick. This created a lot of work for us to do at home. This part of the project was definitely not ideal, but it taught me about the importance of effort. There are still things that I think I need to do better though. I feel like I need to be more empathetic towards the needs of the people in my group. I also need to work on my cooperation and group work. This Murder Mystery project definitely taught me many things and was a lot of fun!
Looking back on the project, it was definitely a great learning experience for me. The investigation portion of the project went well. My group was able to find good evidence and work towards putting it together into a case. This part of the project taught me about forensic science and the world of criminal investigation. However, there were definitely a few bumps in the road. One example of this is our petty squabbles. Although, we got along overall and were able to build a solid case, we would fight over dumb stuff, such as who would get the case file at the beginning of the day. This taught me about collaboration. Another peak came when we delivered the presentation. The judges understood what we said and we were able to answer their questions. This part of the project taught me about public speaking and helped me understand professional viewpoints on criminal cases. Another pit occurred in the absences from the project. During this project, there were a few trips from other classes and people calling in sick. This created a lot of work for us to do at home. This part of the project was definitely not ideal, but it taught me about the importance of effort. There are still things that I think I need to do better though. I feel like I need to be more empathetic towards the needs of the people in my group. I also need to work on my cooperation and group work. This Murder Mystery project definitely taught me many things and was a lot of fun!